What is Perfusion?

In construction engineering, pouring refers to pouring the mixed concrete into a mold. The mold here may refer to a pile hole that has been dug or a column template and a beam template that have been assembled. During the construction process, the concrete pouring must meet the following requirements: the concrete is transported directly to the construction site by a concrete truck, and then the concrete is pumped and continuously poured; the retarded soil is added to the concrete to ensure the quality of the concrete Consistent with the design requirements; before sinking the catheter, the tightness and firmness of the connecting part of the catheter must be inspected in detail to avoid leakage and air leakage ^[1] .

In civil engineering construction, pouring simply means pouring the prepared concrete into the assembled formwork. For tall buildings or deep piles, construction is generally carried out by pumping and pouring. Grouting generally requires grouting pipes to convey the concrete.

Grouting pipe refers to the pipe used for grouting.

The grouting pressure and time need to be reasonably controlled during the grouting construction. The grouting pressure should be determined according to the pressure of the pressure water test and the local geological conditions. The pressure should also be determined during the grouting process. The pressure is adjusted according to the different lengths of the pile body. If necessary, trial injection construction can also be performed to determine the optimal grouting pressure. If during the grouting process the pressure is too low, or the phenomenon of grouting or stringing occurs, intermittent grouting can be used, and the interval between each grouting is controlled between 30 and 60 minutes. The grouting operation can only be stopped after the amount of grouting near the pile reaches the design requirements. After the grouting construction is completed, inspections need to be performed in accordance with relevant technical indicators to ensure that the piles are effectively reinforced.

Bored cast-in-situ pile refers to a cast-in-situ pile in which a pile hole is drilled at a pile site by using drilling machinery. There are many types of drilling machines, including auger drills, submersible drills, and impact drills. The former has a smaller diameter and a shallower depth and is suitable for all types of soil above the groundwater level; the latter drills into the mud for drilling. Drilling in clay can inject fresh water into the pile hole to protect the wall to prevent hole collapse; when drilling in sand, the prepared mud should be injected. Drilling is required to drill to the designed depth. Prevent settling of soil residue to increase pile settlement. Reaming equipment at the bottom of a pile hole can increase the bearing capacity of the pile. Drilling should prevent hole collapse and deflection. Drill holes in miscellaneous filling or soft soil layers. Steel protection cylinders should be buried at the piles to locate, protect the orifices and keep the mud level higher than underground. After the holes are cleared, the reinforced steel frame and the poured concrete are hoisted, and the hydraulic concrete needs to be poured by the conduit method in the mud. There is no vibration and no soil compaction during construction, and it can be used in various soils. Bored cast-in-situ piles have no noise, no vibration, and have a small impact on the environment. The maximum diameter is 3 to 4 meters and the bearing capacity is large. With the construction of expressways and high-rise buildings, it is a form of foundation bearing capacity. It is widely used. However, since the construction of bored cast-in-place piles is mostly carried out underwater, the construction process cannot be observed, and the pile cannot be excavated and accepted. The main process is hidden, and the quality control is difficult. There are many quality control points, and problems in any link during construction may affect the quality of pile formation ^[2] .